The COVID-19 pandemic continues to create stress and anxiety for many Canadians, particularly those who do not have ready access to their regular support networks. Through the Wellness Together Canada online portal, people of all ages across the country can access immediate, free and confidential mental health and substance use supports, 24 hours a day, seven days a week. |
OTTAWA, ON, July 13, 2021 /CNW/ - Testing for SARS-CoV-2 infection has become more available as the pandemic has continued, but we know that not everyone who has experienced an infection has been tested – either because they had few or no symptoms, or because a testing facility was not accessible. To measure the true burden of infection and to better understand who has been affected, many countries have used serosurveillance, which is a method of testing a representative sample of the population to estimate how many have antibodies to the virus in their blood. The presence of these antibodies indicates that the person has been exposed to the virus, or developed antibodies in response to vaccination.
The Public Health Agency of Canada, through the COVID-19 Immunity Task Force, has supported serosurveillance in several communities and settings. From November 2020 to April 2021, Statistics Canada conducted a large representative study, the Canadian COVID-19 Antibody and Health Survey (CCAHS). Data were collected from more than 10,000 people across all provinces and territories, aged 1 year and older using a questionnaire and a self-administered Dried Blood Spot (fingerprick) sample for testing.
During the study period, about 2.6% of people across Canada developed antibodies from a past infection and another 1% had antibodies from vaccination. About one third of respondents who had antibodies had never been tested for COVID-19 with a nasal or throat swab, and most of those reported that they never had symptoms of illness. This illustrates that SARS-CoV-2 transmission was happening in Canada among people who didn't know they were infected and could have spread it to others.
The CCAHS has shown that people over 60, living in their own homes and communities, have experienced fewer SARS-CoV-2 infections than their younger neighbours: only 1.4% of people aged 60 years and older, compared to 2.9% of those aged 20 to 59 years, had SARS-CoV-2 antibodies in their blood. CCAHS has also illustrated again who is at increased risk of infection: 4.3% of people in Canada who belong to visible minority communities had antibodies, compared to 2.1% among non-visible minorities. The visible minority population was also less likely than the non-visible minority to have acquired antibodies from immunization (0.5% versus 1.2%).
Since CCAHS completed data collection in April, many more Canadians are now vaccinated, including over 79% of those aged 12 years or older who have received at least one dose and over 50% who are fully vaccinated as of July 13, 2021. Information from this and future serosurveillance, along with vaccine coverage studies and COVID-19 case data, will help us estimate the level of protection achieved in the Canadian population. Despite the heavy toll that the COVID-19 pandemic has taken, seroprevalence estimates from more than 100 other countries are similarly low and comparable to Canada's. However, the risk of illness is not equally distributed across society, and safe and effective vaccines remain our best public health intervention to achieve widespread and lasting protection.
As COVID-19 activity continues in Canada, we are continuing to track key epidemiological indicators to monitor trends and quickly detect emerging issues of concern, including to better understand the impact of circulating virus variants. The Public Health Agency of Canada (PHAC) is also providing regular updates on COVID-19 vaccines administered, vaccination coverage and ongoing monitoring of vaccine safety across the country. The following is the latest summary on national numbers and trends.
Since the start of the pandemic, there have been 1,421,108 cases of COVID-19 and 26,438 deaths reported in Canada; these cumulative numbers tell us about the overall burden of COVID-19 illness to date. Variants of concern (VOCs) represent the majority of recently reported COVID-19 cases, including four VOCs (B.1.1.7 (Alpha), B.1.351 (Beta), P.1 (Gamma), and B.1.617.2 (Delta)) that have been detected in most provinces and territories. While the Alpha variant still accounts for the majority new cases nationally, the Delta variant has increased and now accounts for the majority of new COVID-19 cases in some areas, such as in Ontario. As all viruses change over time, including the SARS-CoV-2 virus that causes COVID-19, new and emerging variants are expected. PHAC, in collaboration provincial and territorial partners and CanCOGeN, monitor for these changes by sequencing a percentage of all COVID-19 viruses from positive cases. While this percentage has varied over time, since mid-May, over 70% of all positive cases have been sequenced. Regardless of which viruses are predominating in an area, we know that vaccination, in combination with public health and individual measures, continue to work to reduce the spread of COVID-19.
While the latest national-level data show a continued decline in disease activity with an average of 451 cases reported daily during the latest 7 day period (July 6-12), the rate of decrease may be slowing. As public health restrictions are eased, some increase in cases, particularly among unvaccinated populations, is not unexpected. The latest provincial and territorial data indicate that an average of 692 people with COVID-19 were being treated in Canadian hospitals each day during the most recent 7-day period (July 6-12), which is 14% fewer than last week. This includes, on average 329 people who were being treated in intensive care units (ICU), 18% fewer than last week and an average of 9 deaths were reported daily (July 6-12).
Administration of first and second doses of COVID-19 vaccines is continuing across the country and there is optimism that widespread, stronger and longer lasting immunity can be achieved by fully vaccinating a high proportion of Canadians. For more information regarding the risks and benefits of vaccination, I encourage Canadians to reach out to your local public health authorities, healthcare provider, or other trusted and credible sources, such as Canada.ca and Immunize.ca.
Canadians can access information on Canada.ca to understand the benefits of being vaccinated against COVID-19, find guidance on life after vaccination and utilise free interactive risk assessment tools to aid in informed decision-making and understanding COVID-wise precautions to lower the risks in different settings. However, as jurisdictions begin to ease restrictions, risks and circumstances are not the same everywhere and following local public health advice continues to be important, regardless of your vaccination status. While COVID-19 is still circulating in Canada and internationally, core public health measures and individual protective practices can help us to reduce the spread: stay home/self-isolate if you have symptoms; be aware of risks associated with different settings; avoid all non-essential travel; and maintain individual protective practices such as physical distancing and wearing a well-fitted and properly worn face mask, as appropriate.
Canadians can also go the extra mile by sharing credible information on COVID-19 risks and prevention practices and measures to reduce COVID-19 in communities. Read my backgrounder to access more COVID-19 Information and Resources on ways to reduce the risks and protect yourself and others, including information on COVID-19 vaccination.
SOURCE Public Health Agency of Canada
Media Relations, Public Health Agency of Canada, 613-957-2983, [email protected]
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